1. Field of the Invention
The invention relates to a magic slate capture and display device. In particular, the invention relates to a reusable medium and a device using reusable medium to create erasable images.
2. Description of the Related Art
Existing media such as conventional paper may be printed using dot matrix, impact or ink jet printers or laser printers. Either single sheets or a continuous stream of paper may be fed into the device for printing images such as text data or graphics. In virtually all cases, the ink is permanent. Once such images have been formed on the paper, the printed surface of the paper cannot be printed on again. An ongoing supply of new paper is required. In the case of a device such as a printing calculator, a roll of paper must be replenished as the paper supply is consumed. In both of these applications, there is often no need to keep the printed output more than a short time. Materials are consumed (paper and ink) and cannot effectively be reused.
A toy called the Magic Slate has entertained children for many generations. The toy comprises a hard waxy black base surface, a thin gray film and a thicker clear film on top. Images can be drawn on the top surface of the clear film using a stylus or other pointy pressure tip device. When pressure is applied to the top surface using the stylus, the gray film sticks to the waxy black base material at the point the pressure is applied. This temporary adhesion results in the gray film becoming darker. The wax at the point of adhesion provides an optical path to the black substrate and attenuates reflected light. The thick top layer protects the thin gray layer from damage. To erase the image, the gray film is manually lifted away from the black base, breaking the temporary adhesion.
The above-described toy, however, only allows the forming of images via a hand-held stylus. Thus, the quality and throughput of the images is severely limited by the ability and the efforts expended by the individual forming the image. Also, control of the stylus, regardless of the ability of the user, is limited by the size of the stylus and the relation of the stylus to the amount of pressure required to form the adhesion. Thus, the above-described toy is impractical to form print-quality text and graphic images.
A device according to the present invention comprises an erasing portion; and a writing portion; wherein the erasing portion comprises a separator for separating at least two layers of the reusable medium; and wherein the writing portion comprises automatic pressure applicators for applying pressure but no ink to the reusable medium, thereby forming an image on the reusable medium. Additional images and annotation can be added manually after the printing process.
In a further embodiment of the present invention, a reusable medium according to the present invention comprises a first layer of a first material; a second layer of a second material; and a layer of adhesive disposed on the first layer and placed between the first layer and the second layer; wherein one of the first layer and adhesive layer contains a color and wherein the layer of adhesive causes an image to be formed on the second layer when the second layer is selectively contacted to the first layer, and wherein the layer of adhesive comprises a plurality of separated regions.
In a further aspect of the present invention, a plurality of the regions of the adhesive may contain a different color.
In a yet further embodiment of the present invention, a method is provided of forming images on a reusable medium. The method comprises erasing the reusable medium by separating at least two layers of the reusable medium, and controlling a plurality of pressure applicators to apply pressure on the reusable medium to create an image.